body {
    font-family: sans-serif;
    border: 2px solid #2792c6;
    border-radius: 5px;
    padding: 5px;
    color: #0000ff;
}

a:visited {
    color: #cd853f;
}

#mul_table {
    text-align: center;
    margin: 0 auto;
}

#each_table {
    display: inline-block;
    padding: 5px;
    margin: 5px;
    border: 1px solid brown;
    color: darkslategrey;
}